ChemCom: Spring Semester Final Exam Practice Test

Battery Unit Directions: Use the following lab data to answer question 1. 

 Battery   Metal #1  Metal #2  Voltage Measured 

Potato Clock  Magnesium  Silver  3.16 V 

1. Use the table below to calculate the theoretical voltage of the battery in the potato

clock above. (Theoretical = Eogain ­ Eolose) 

Water Quality Unit Directions: The WQI is calculated using nine different tests. For the questions below; describe what each WQI test measures.

WQI Test What does this test measure?

2. pH

3. Turbidity

4. fecal coliform

5. Dissolved Oxygen (D.O.)

Directions: The WQI is calculated using nine different tests. For the questions below, describe how each test is performed. Each choice may only be used once. NOT ALL ANSWER CHOICES WILL BE USED.

WQI Test Describe how the test is performed.

6. Turbidity

7. Fecal Coliform

8. Total Solids

9. Temperature

Directions: Low quality (Q) values by any of the nine tests that make up the WQI can cause problems in a lake or river. Identify the described problems below with the likely cause. 10. Water Problem: Local fishermen have contracted typhoid fever and hepatitis. Local kids

playing in the river have reported numerous ear infections and dysentery. Contact with the water seems to be making people sick.

What test is most likely showing a low Quality Value?

11. Water Problem: Entire lake appears to lack life of any kind. Lake is completely clear but

has nothing living. Tests also show a high level of heavy metals in the water.

The water most likely is suffering from what?

12. Water Problem: Water appears very muddy. Visible silt and floating particles in the water. The bottom cannot be seen even in shallow water.

What test is most likely showing a low Quality Value?

13. Water Problem: The water is very warm. Water is clear but there are dead fish. The only

fish alive seem to be catfish and bullheads.

What 2 tests are most likely showing a low Quality Value?

Directions: The environment surrounding a stream or creek can often have a direct impact on some of the nine tests used to measure the WQI. For questions 14 & 15 decide which environmental factor described below with the likely impact it will have on the lake or river. 14. A local creek is surrounded by farms. The farmers are often seen using fertilizers on the

cornfields directly next to the stream.

What environmental factor will likely have an impact on the stream?

15. A dairy farm has a creek in the middle of the field where cows and sheep can be seen

grazing daily. Often the cows can be seen dropping cow pies (poop) into the river.

What would be the most IMMEDIATE effect on the water be? Total Solids: 16. Using the data below and the total solids formula, what would be the calculated level of

total solids in this sample? Total solid scum formula  Mass of residue (g) / Sample V olume (mL)  )  x 1, 00, 00 mg2/g L  ppm total solids( 0 0 =  

Total solids data Water poured into beaker: 185.0 ml Mass of beaker with dried solid: 112.15 grams Mass of clean beaker: 112.13 grams

Directions: Use the Quality graph and the lab data below to answer questions 17-19.

Lab Data: Nitrate Testing Nitrate Level = 1 ppm 17. What is the Q value for the sample tested?

18. How would you rate the quality of the water?

19. What is the WQI score for this sample?

UNIT 2D Questions Directions: Use the graph below to answer questions 20-22.

Graph Showing the Projected Increase in the Temperature of the Oceans

20. Write a 1 sentence story of the graph, describing the relationship between the change in ocean temperature vs. the year. 21. What is the main reason the temperature of the oceans is increasing? 22. How much is the temperature of the ocean projected to change between 2030 and 2050? (Use the graph above to find your answer)

Directions: Use the graph below to answer questions 23-25.

Graph Showing the Current and Predicted CO2 Levels in the Atmosphere 23. What is the projected carbon dioxide level in the atmosphere in the year 2010? 24. How much is the carbon dioxide level going to change between 2020 and 2060? 25. Give at least two reason for why the carbon dioxide levels are increasing in the atmosphere? 26. What does “ppm” stand for?

Directions: Use the graph below to answer the following questions 27-30.

27. What is the slope of the graph above? Remember to include units. (Show your work) 28. Write a “For Every” statement using your slope for the graph above. 29. Based on the graph above, if the carbon dioxide level changes by 80 ppm in the future, the pH of the ocean will drop to about what number? 30. Use the Lundgren Equation to calculate how many more times acidic the ocean will become if the carbon dioxide level increases by 80 ppm? (Lundgren Equation =  Change in acidity = 10   pH)Δ  

Directions: Ocean Acidification The graph below shows the pH of a beaker of salt water after a student added solid dry ice (CO2) to the beaker. Use the graph below to answer the following questions 31-33.

31. At the end of the experiment (Time = 10 min), the sample would be classified as an acid, base, or neutral? Why? 32. What was the of the ocean water during the experiment?pH  Δ

33. What substance is produced when CO2 in the atmosphere reacts with ocean water? Write the chemical equation for this reaction.

Directions: The graph below shows the pH of two simulated lakes after they received heavy doses of acid rainfall. Use the graph below to answer the questions 34-37.

34. What was the final pH of the sand lake after 100 drops of acid rain were added? 35. Which lake would be considered an acid at the end of the experiment? 36. Which lake dropped to a pH that would kill all of the life in the lake at the end of the experiment? 37. What was the of the limestone bottom lake during the experiment?pH  Δ

Directions: The diagram below shows a screenshot of the Micro pH - PhET. Use the diagram below to answer questions 38-41.

38. Which of the liquids listed would be classified as a base?

39. A student did an experiment to determine the pH of all the substances listed above. What would be the independent variable in their experiment? What would be the dependent variable? 40. Which of the following compounds represents an acid

a. NaOH b. HF c. NaCl d. Mg(OH)2

41. Which of the following compounds represents a base a. NaCl b. HF

c. HCl d. NaOH

Unit 2C Questions Directions: Use the graph below to answer questions 42-4. 42

42. On the altitude vs. temperature graph above please label the troposphere, the mesosphere,

and the stratosphere. 43. What is the name of the layer of the atmosphere that we live when on the surface of the Earth? 44. What layer of the atmosphere did Felix Baumgartner jump from? 45. What was the temperature outside of the balloon when Felix jumped? 47. What is the difference in the temperature of the atmosphere when you compare where Felix jumped to the surface of the Earth? 48. What are the two most abundant gas in the atmosphere? What are there relative amounts?

Directions: Use the graph below to answer questions 49-52.

49. Based on the altitude and pressure graph above, which is the relationship between

altitude and air pressure? 50. If Felix did not wear a spacesuit, what would have happened to his blood when he

stepped outside of the capsule to jump? Why?

51. Felix jumped from about 40 km above the Earth. What was the approximate pressure

around the balloon when he jumped? 52. At what altitude what the air pressure be 405 mmHg?

Directions: Use the graph below describing changes in the Earth’s atmosphere to answer questions 53-55.

53. Based on the graph, rank the gasses from the gas that traps the most infrared radiation, to

the gas that traps the least infrared radiation. a. most CH4, CO2, H2O, N2 least b. most CO2, CH4, N2, H20 least c. most N2, H2O, CO2, CH4 least d. most CO2, H2O, CH4, N2 least

54. Which of the greenhouse gases tested above are produced when hydrocarbons like coal, gasoline and natural gas are burned? 55. Which of the above gases are considered to be greenhouse gases?

Directions: Use the data table and graph below to answer questions 56-57.

56. Which set of data would show the temperature of the Earth’s atmosphere if the amount

of greenhouse gasses in the atmosphere was a lot higher than today’s levels? a. A b. B c. C

57. Based on the data table, about how much has the carbon dioxide increased “today”

compared to the carbon dioxide level in 1750?

Directions: Use the data table and graph of the Carbon Dioxide levels from Mauna Loa to answer questions 58-59.

58. What was the level of carbon dioxide in the atmosphere in 1800 before people during the industrial revolution began burning coal? 59. In 2015 the carbon dioxide level in the atmosphere hit 400 ppm. How much CO2 has been added to the atmosphere since 1900? 60. What are the products for all hydrocarbon combustion reaction? 61. The chemical equation for burning gasoline is below. Why does burning fossil fuels like

gasoline and coal contribute to global warming? 2 C8H18 + 25 O2 --> 18 H2O + 16 CO2

Directions: Use the equations and the graph below to answer the questions 62-65:

. 62. Which color photons of light on the spectrum above would have the highest energy? 63. Estimate the wavelength of the photons of light making the 0.9 intensity peak in the yellow

zone.

64. The photons captured by the spectrovis were generated by exciting the atoms of the different chemicals with energy. Which subatomic particle gets pushed up to higher energy levels, then falls emitting photons of light during the experiments?

65. Calculate the energy in a photon of infrared light that has a wavelength of 7.8 x 106 nm.

Unit 2B Questions:

Directions: Match the names of the phase changes below to the descriptions in questions 66-70.

a. condensation d. vaporization (boiling) b. freezing e. sublimation c. melting

66. Dry ice changing from a solid to a gas at room temperature

67. Water changing from a liquid into a solid

68. A liquid that is heated until gas bubbles form throughout the sample 69. When water vapor is cooled and forms water droplets on the surface of the container. 70. After leaving your water bottle in the freezer overnight it turns into ice. Directions: Match the description of the flow of energy below to the descriptions in questions 71-72.

a. Energy must be added c. Energy does not get added or released b. Energy is released

71. Freezing a glass of water

72. Boiling a pot of water

Directions: Use the graph below to answer questions 73-77.

73. Label what states of matter are present at each segment on the graph above. 74. The melting point temperature for the substance above is what? 75. The boiling point temperature for the substance above is what?

76. What is happening to the sample between letters B and C

77. In what segment are both solid and liquid phases present?

Directions: Use the graph below to answer questions 78-81.

78. Label the following on the graph above: normal melting point, normal boiling point, critical point, triple point, the region where only solid exists, the region where only liquid exists, and the region where only gas exists.

79. What phase would the sample be in at a pressure of 50 kPa and a temperature of -10 oC.

80. What pressure and temperature would the triple point exist at?

81. If the pressure stayed constant at 40 kPa, and the temperature changed from 50 deg C to 0 deg C, what phase change would occur?

Directions: Use the graph below to answer questions 82-83.

82. According to the graph above, what percent solution of ethylene glycol will protect your engine

from the coldest temperatures? 83. According to the graph above, what percent solution of propylene glycol will protect your engine

from the coldest temperatures?

84. According to the graph above, what is the OEM Recommended Range for percent glycol? 85. Which glycol solution has a higher freezing point in the OEM Recommended Range?